Does the outcry over airport pat-down searches ordered by the Obama administration show Americans have reached their limit in the concessions they’ll make in the fight against terrorism? Or is it a fleeting over-reaction to a few incidents of bad behavior by Transportation Security Agency screeners?

Those questions were unresolved Monday as the controversy over airport screening raged on and millions of Americans prepared for what is traditionally the busiest travel time of the year.

For the moment, conservatives often critical of what they regard as the Obama administration’s inadequate response to terrorism and liberals who have been railing for years against a variety of intrusive measures undertaken by the national security apparatus since the September 11 attacks seem to have reached a rare consensus.

“I believe this is a tipping point,” said Debra Burlingame, a vocal advocate for tough anti-terrorism policies. Burlingame – whose brother was the pilot of the hijacked American Airlines Flight 77 which crashed into the Pentagon on 9/11 – was outraged after undergoing the new TSA pat-downs.

“I was not prepared for it…I’ve been patted down a lot of times but never like this,” recalled Burlingame. “I had to tell myself not to cry…..It’s about having a keen sense of your human dignity being violated.”

The new measures are prompted in part by a terrorist incident last Christmas, in which a Nigerian man allegedly tried to destroy a US-bound jetliner by detonating explosives sewn into his underwear. Burlingame said the high-tech body-scans and thorough frisking – which some have compared to sexual molestation – are more intrusive than effective, particularly in the hands of TSA agents with little expertise in detecting well-hidden contraband.

As the backlash has grown, however, conservative commentators such as Charles Krauthammer and George Will have found themselves on the same page with liberal writers such as James Fallows.

“Pigs fly. Also, I agree with Charles Krauthammer,” Fallows wrote on the Atlantic’s web site Monday. He went on to indicate he concurred with what conservative radio host Mark Steyn called the “stupid ineffectiveness” of broadly-applied, assertive pat-down searches.

The abrupt move to detailed body scanning and aggressive pat-downs – along with security requirements to remove shoes, ditch containers with more than three ounces of liquid and remove belts to pass through security – has left travelers fed up, according to Bruce Hoffman of Georgetown University.

“We’ve reached a point where people are saying: where does it stop?” Hoffman said. “To me it’s not a case of immaturity at all...I take this as people asking for prudence and more information.”

However, some security experts don’t think fickle Americans suddenly have a more sophisticated view of a terrorist threat, or that the travelling public has concluded the long odds of a devastating attack aren’t worth an invasion of their privacy.

“If I thought this was the American public making a rational decision weighing the risks and the benefits, saying, ‘We will accept X percentage of risk of catastrophic attack because we’re unwilling to pay the price of degraded personal privacy,’ that would be a rational judgment and you could set that dial anywhere you wish, [but] I suspect that is not what’s happening,” said Paul Rosenzweig, a former federal prosecutor and a top official at the Department of Homeland Security during the Bush administration.

“What’s happening is a reaction against the intrusiveness. They’ve decided they don’t like that part of it but haven’t considered the other side of the equation,” Rosenzweig said. If another airline bombing attempt happens, he added, “instead of looking in the mirror and saying, ‘This is part of the bargain,’ [the public is] going to say ‘Where is my perfect security President Obama, or President Pawlenty?’ or whatever.”

“I think this is unfortunately a bit of a case of the American public wanting to have their cake and eat it, too,” he said.

New polling shows broad support for the new scanning machines but a deep divide over the more thorough pat-down searches. In an ABC News/Washington Post poll released Monday evening, 64% of Americans backed the scanners and only 32% said they went too far. But the pat-downs split Americans, with 48% agreeing they are justified and 50% finding them excessive. Opposition rose somewhat among regular travelers and was lower among those who rarely or never fly.

“It’s the wingers against the middle in this case,” said Stewart Baker, a former undersecretary of Homeland Security for policy. If a bombing happened after standards were relaxed, he said, there would be a backlash against what would be viewed as lax security – and it would be widespread and far more intense.

“It’s so obvious what Al Qaeda will do” if the administration changed course, Baker said. “Anybody who votes to end it would be held accountable if that happens.”

Nevertheless, Marc Rotenberg of the Electronic Privacy Information Center, a long-time critic of body-scan machines, said the public response to an airline bombing would depend on how explosives made it on board – and could expose the utter futility of trying to guard against all terrorist attacks.

“Which public reaction are you speaking of?” said Rotenberg, asked about the response a successful attack might trigger. “The one where the cargo is not adequately screened, a plane blows up, and people realize that body scanners were worthless? Or the one where explosives are concealed in a body cavity, a plane blows up, and people realize that body scanners were worthless?”

After standing by the new procedures, TSA director John Pistole on Sunday issued a statement saying the administration was open to adjustments, based on passenger feedback. Secretary of State Hillary Clinton seemed to join in the public outcry, saying in a weekend interview that she wouldn’t like to go through an aggressive pat-down. “Who would?” she asked.

By Monday, Pistole was careful to say that while the administration is listening, nothing had actually changed.

“There is a continual process of refinement and adjustment to ensure that best practices are followed,” Pistole told reporters at a breakfast hosted by the Christian Science Monitor. "Nothing will change, as far as today. The focus is on how can we best detect that and recognizing we face challenges with additional holiday travelers and trying to make sure we are getting everybody safely and securely to the destination on a timely basis.”

In fact, the controversy has spurred just one significant adjustment: airline pilots are now exempt from the new security measures.

One former official in regular contact with the Obama administration told POLITICO that the White House is worried about the political blowback they’d get if an attempted bombing happened after they adjusted the new process – and noted that Al Qaeda has been known to strike during the holiday season.

“They’re in a tough spot,” the ex-official said. The terror networks that helped plan the last three attempted bombings, the official said – in the airliner on Christmas Day, in Times Square during the summer and on a cargo jet bound to the US from Yemen last month – is still active and “clearly adaptive.”

Another former official, speaking on condition of anonymity, faulted a “botched roll-out” for the controversy, and blamed the White House for “a horrible education process.” Pistole conceded Monday that the administration considered announcing the changes in advance, but decided it might tip their hand to terrorists.

Last January, after Umar Farouk Abdulmutallab – the Christmas Day “underwear bomber” – was apprehended, White House Spokesman Robert Gibbs was asked if the incident meant Americans should expect “embarrassing procedures” at U.S. airports. Gibbs said the administration could “easily achieve a balance that allows us not to give up our privacy, but at the same time protects us from those that seek to do us harm.”

On Monday, Gibbs was less sanguine: finding that sweet spot, he said, is “not an easy task,” he told reporters. “That's a balance that we will continue to search for.”